The present invention relates to recording medium read devices. More particularly, it relates to a recording medium read device with an improved positioning mechanism for positioning a disc at a clamp position of a turntable and an improved detector mechanism for detecting the positioning, when a disc such as a compact disc (CD) has been loaded therein.
Recently, read devices have become widespread which employ discs such as CDs or DVDs as a recording medium. Among these disc read devices, for example, a vehicle-mounted device (a CD player) 1 as shown in FIG. 14 has been developed to enjoy music inside vehicles.
Such a device is adapted to perform positioning by centering each of the disc 8 cm in diameter and the disc 12 cm in diameter, loaded into the read device, on the read mechanism.
An example of the centering mechanism comprises a pair of right and left centering arms, provided on a clamper arm, with a positioning portion for positioning a loaded disc on the read mechanism, and a centering lock arm for positioning the positioning portion of the centering arm at a predetermined position.
The positioning portion is adapted to be on standby at a position where the 8 cm disc can be positioned on the read mechanism and adapted to be pushed by a 12 cm disc to move to a rear portion of the device when the 12 cm disc is loaded. That is, when the 8 cm disc is loaded, the centering arms are locked by the centering lock arm to position the 8 cm disc on the read mechanism. When the 12 cm disc is loaded, the centering arms are unlocked to position the 12 cm disc on the read mechanism.
In addition, a detector member for detecting that a disc has been positioned on the read mechanism is provided on the aforementioned positioning portion. The detector portion is adapted to move, by the movement of the positioning portion, between the position for detecting the 8 cm CD and the position for detecting 12 cm CD.
However, in the aforementioned example of the prior art, the aforementioned members are required for positioning the 8 cm and 12 cm discs and for detecting that the disc has been positioned, thus increasing the number of parts used.
In addition, the device is adapted to allow the positioning portion and the detector portion to move a great deal, thereby adversely affecting the positioning accuracy for positioning each type of disc.
The present invention was suggested to solve these problems, and an object of the present invention is to provide a recording medium read device which requires less number of parts, which can position a disc transported into the device at the read position with accuracy, which can detect with accuracy that the disc has been positioned, and which can further reduce the device in size.
To achieve the object, the invention according to claim 1 provides a recording medium read device comprising a loading opening for allowing a recording medium of a smaller and a larger diameter to be loaded therethrough and a read mechanism for reading the recording medium. The invention is characterized in that a positioning means for positioning the recording medium loaded into the loading opening to a predetermined position relative to the read mechanism is provided inside the device; the positioning means has a first positioning portion for positioning a recording medium of the smaller diameter and a second positioning portion for positioning a recording medium of the larger diameter in the same member; and when a recording medium of the larger diameter is transported, the first positioning portion is retreated from a transport passage for the recording medium of the larger diameter.
According to the invention of claim 1, the first and second positioning portion are formed in the positioning means.
When a recording medium of a smaller diameter transported into the read mechanism, for example, a recording medium 8 cm in diameter is positioned, the first positioning portion is used for positioning the medium.
When a recording medium of a larger diameter, for example, a recording medium 12 cm in diameter is positioned, the second positioning portion is used for positioning the medium.
Moreover, when the recording medium of the larger diameter is transported, the first positioning portion is retreated from the transport passage.
Consequently, the positioning portions for each type of recording medium can be formed on the same member, thereby reducing the device in size and the number of parts.
The invention according to claim 2 is characterized in that the positioning means is movable so that the first positioning portion is retreated in a direction generally perpendicular to a recording surface of the recording medium being transported.
According to the invention of claim 2, the positioning means is moved so that the first positioning portion is retreated in a direction generally perpendicular to a recording surface of the recording medium being transported, thereby positively preventing interference with the recording medium being transported.
The invention according to claim 3 is characterized in that the second positioning portion is located at a position for positioning the recording medium of the larger diameter after the first positioning portion has been retreated.
According to the invention of claim 3, the second positioning portion is adapted to be located at a position for positioning the recording medium of the larger diameter after the first positioning portion has been retreated. This makes it possible to positively position the transported recording medium of the larger diameter on the read mechanism.
The invention according to claim 4 is characterized in that the positioning means is disposed in a deep portion of the device and is pivotably tilted about a shaft generally parallel to the recording surface of the recording medium.
According to the invention of claim 4, the positioning means is adapted to be disposed in a deep portion of the device and pivotably tilted about a shaft generally parallel to the recording surface of the recording medium. This allows the positioning means to move only a small amount particularly in the vertical direction of the device, thereby reducing the device in size and particularly reducing it in thickness.
The invention according to claim 5 is characterized in that the positioning means can be moved by a transport force of the recording medium of the larger diameter.
The invention according to claim 6 is characterized in that the device further comprises a contact member for contacting with a rim of the recording medium of the larger diameter and the contact member moves to allow the positioning means to move.
The invention according to claims 5 and 6, the positioning means is adapted to be tilted when the recording medium of the larger diameter is transported. Particularly, since the transportation of the recording medium of the larger diameter can be detected by the contact member, detection and control can be mechanically carried out, thereby providing more ensured detection than with sensors.
The invention according to claim 7 provides a recording medium read device comprising a loading opening for allowing a recording medium of a smaller and a larger diameter to be loaded therethrough and a read mechanism for reading the recording medium. The invention is characterized in that detector means for detecting that the recording medium loaded into the loading opening has been positioned to a predetermined position relative to the read mechanism is provided inside the device; the detector means has a first detector member for contacting a rim of the recording medium of the smaller diameter and a second detector member for contacting a rim of the recording medium of the larger diameter; and when the recording medium of the larger diameter is transported, the first detector member is retreated from a transport passage for the recording medium of the larger diameter.
According to the invention of claim 7, the first and second detector member makes it possible to detect that a recording medium of a smaller diameter such as a recording medium 8 cm in diameter or a recording medium of a larger diameter such as a recording medium 12 cm in diameter has been positioned on the read mechanism. Furthermore, the first detector member is adapted to be retreated from the transport passage of the recording medium of the larger diameter when the recording medium of the larger diameter is transported.
This makes it possible to perform read action accurately and quickly after the recording medium has been loaded.
In addition, the first and second detector member are located in the transport passage of the recording medium. The detector member is adapted to be retreated from the transport passage of the recording medium of the larger diameter according to the recording medium to be loaded, thereby reducing the device in size.
The invention according to claim 8 is characterized in that the detector means is movable so that the first detector member is retreated in a direction generally perpendicular to a recording surface of the recording medium being transported.
The invention according to claim 9 is characterized in that the second detector member is located at a position for positioning the recording medium of the larger diameter after the first detector member has been retreated.
According to the invention of claims 8 and 9, the detector means is moved so that the detector member is retreated in a direction generally perpendicular to a recording surface of the recording medium, thereby preventing the detector means from interfering with the recording medium to allow the recording medium of a smaller and larger diameter to be positively positioned. This makes it possible to read appropriately the recording medium.
The invention according to claim 10 is characterized in that the detector means is disposed in a deep portion of the device and is pivotably tilted about a shaft generally parallel to the recording surface of the recording medium.
According to the invention of claim 10, the detector means is pivotably tilted, thereby allowed to rotate (move) slightly. This makes it possible to minimize the space for the movement and thus reduce the device in size.
The invention according to claim 11 is characterized by further comprising a positioning means having, in the same member, a first positioning portion for positioning the recording medium of the smaller diameter and a second positioning portion for positioning the recording medium of the larger diameter and in that the first detector member is provided by being slightly protruded from the first positioning portion and the second detector member is provided by being slightly protruded from the second positioning portion.
The invention according to claim 12 is characterized in that the detector members and the positioning means are provided on the same support means.
The invention according to claim 13 is characterized in that the first detector member and the second detector member are formed on the same detector arm and the detector arm is pivotably journaled.
According to the invention of claims 11, 12, and 13, the first positioning portion for positioning the recording medium of the smaller diameter and the second positioning portion for positioning the recording medium of the larger diameter can be formed of the same member. This makes it possible to reduce the number of parts used and the device in size, and simplify the device.
The invention according to claim 14 is characterized by further comprising a transmission member for moving a predetermined distance by rotation of the detector arm and in that the transmission member moves to cause the support member to move in a direction to release the contact between the positioning means from the recording medium.
According to the invention of claim 14, the transmission member is adapted to move to cause the support means to move in such a direction as to release the contact between the positioning means and the recording medium. This makes it unnecessary to use a complicated sensor or the like and improves the accuracy of operation. Furthermore, it is made possible to reduce the cost and size of the device.